ACTUATOR SYSTEM FOR ROTATING VALVE PIN
20180141248 ยท 2018-05-24
Inventors
Cpc classification
B29C2045/2882
PERFORMING OPERATIONS; TRANSPORTING
B29C45/231
PERFORMING OPERATIONS; TRANSPORTING
B29C45/0046
PERFORMING OPERATIONS; TRANSPORTING
B29C45/7613
PERFORMING OPERATIONS; TRANSPORTING
B29C2045/1794
PERFORMING OPERATIONS; TRANSPORTING
B29C45/30
PERFORMING OPERATIONS; TRANSPORTING
International classification
B29C45/00
PERFORMING OPERATIONS; TRANSPORTING
Abstract
An injection molding apparatus comprising an injection molding machine, a manifold, a closure valve pin, a first actuator having a linear or axial driver, a second actuator comprising a rotor interconnected to either the closure valve pin or to a second valve pin such that either the closure valve pin or the second valve pin is rotatably driven in unison with the rotor around the rotation axis, the closure pin or second pin being disposed and rotatable within the flow of injection fluid flowing through a flow channel leading to a mold cavity.
Claims
1.-16. (canceled)
17. An injection molding apparatus comprising an injection molding machine, a manifold that receives injection fluid from the machine and routes the injection fluid through a flow channel communicating with a gate to a cavity of a mold, a first actuator and a second actuator, a closure valve pin having a pin axis, the closure valve pin being adapted to be controllably driven upstream and downstream along an axial path of travel through the flow channel such that a distal tip end of the valve pin is driven into and out of a position that closes flow through the gate, the first actuator having a linear or axial driver drivable along a reciprocal path of travel coincident or parallel to the axial path of travel, the closure valve pin being interconnected to the first actuator such that the valve pin is driven along the axial path of travel and reciprocally upstream and downstream into and out of the position that closes flow through the gate, the second actuator comprising a rotor having a rotation axis, the rotor being interconnected to either the closure valve pin or to a second valve pin such that either the closure valve pin or the second valve pin is rotatably driven in unison with the rotor around the rotation axis, the closure valve pin or second valve pin that is interconnected to the rotor being disposed and rotatable within the flow of injection fluid flowing through the flow channel, and a controller programmed to controllably drive the first actuator and the linear or axial driver and closure valve pin upstream and downstream between a fully closed position where flow of the injection fluid is stopped, a fully open position at which a rate of flow of the injection fluid is fully open and variable positions intermediate the fully open and fully closed positions at which rate of flow of the injection fluid varies between stopped and fully open.
18. An apparatus according to claim 17 wherein the controller includes circuitry or a program to control the linear and rotational speed, velocity and linear and rotational positioning of the closure valve pin at any and all linear, axial and rotational points and positions during the course of an injection cycle.
19. An apparatus according to claim 17 wherein the controller instructs the actuators to drive the closure valve pin according to any predetermined profile of positions and velocities.
20. An apparatus according to claim 17 wherein the first and second actuators are fluid driven actuators.
21. An apparatus according to claim 17 wherein the first and second actuators are powered by an electric or electronic motor or drive source.
22. An apparatus according to claim 17 wherein the controller is programmed to include instructions that enable to control the position of a tip end of the closure valve pin at any selected profile of positions that vary the rate of flow of the injection fluid through the gate according to any predetermined profile of rates that are less than a maximum rate of flow in the fully open position.
23. An apparatus according to claim 17 wherein the controller is interconnected to one or both of the first and second actuators and which controllably instructs the actuators to drive the one or both of the closure valve pin and the second valve pin according to a predetermined profile of axial travel or rotation.
24. The apparatus of claim 17 wherein the second actuator is mounted such that the axis of the rotor is generally coincident with an axis of an inlet that communicates flow of injection fluid from the machine to the manifold.
25. The apparatus of claim 17 wherein the second actuator is interconnected to the second valve pin.
26. The apparatus of claim 17 wherein the second actuator is mounted to the first actuator and the closure valve pin is non-rotatably interconnected to the rotor of the second actuator, the second actuator and the closure valve pin being adapted to travel along the axial path of travel together with the linear or axial driver of the first actuator.
27. The apparatus of claim 17 wherein the second valve pin comprises an elongated shaft having an outer circumferential surface having discontinuous protrusions, grooves, projections, fins or apertures that are rotatably disposed within the injection fluid flowing through the flow channel, the protrusions, grooves, projections, fins or apertures generating a selected turbulence in the injection fluid flowing through the flow channel when the valve pin is rotated around its pin axis.
28. The apparatus of claim 17 wherein the closure valve pin comprises an elongated shaft having an outer circumferential surface having discontinuous protrusions, grooves, projections, fins or apertures that are rotatably disposed within the injection fluid flowing through the flow channel, the protrusions, grooves, projections, fins or apertures generating a selected turbulence in the injection fluid flowing through the flow channel when the valve pin is rotated around its pin axis.
29. The apparatus of claim 17 wherein the head of the closure pin that is interconnected to the rotor is interconnected such that the pin rotates around the rotation axis of the rotor in unison with rotation of the rotor.
30. The apparatus of claim 18 wherein one or the other or both of the first and second actuators are interconnected to the controller that controllably instructs the actuators to drive the one or the other or both of the closure valve pin and the second valve pin along a predetermined profile of axial travel or rotation.
31. A method of driving a valve pin in an injection molding apparatus comprised of an injection molding machine, a manifold that receives injection fluid from the machine and routes the injection fluid through a flow channel communicating with a gate to a cavity of a mold, a first actuator and a second actuator, a closure valve pin having a pin axis interconnected to at least the first actuator, a controller programmed with instructions adapted to controllably drive the closure valve pin upstream and downstream along an axial path of travel through the flow channel such that a distal tip end of the closure valve pin is driven into and out of a position that closes flow through the gate, the method comprising: interconnecting a closure valve pin to a first actuator having an axial driver drivable along a reciprocal path of travel coincident with or parallel to the axial path of travel such that the valve pin is driven reciprocally upstream and downstream into and out of the position that closes flow through the gate, interconnecting either the closure valve pin or a second valve pin to a second actuator comprising a rotor having a rotation axis such that the closure valve pin or the second valve pin is rotatably driven in unison with the rotor around an axis coincident with or parallel to the pin axis of the closure valve pin, adapting the pin that is interconnected to the rotor to be disposed within the flow of injection fluid that is routed from the injection molding machine to the gate, driving the first actuator to drive its interconnected pin into and out of the position that closes flow through the gate, driving the second actuator such that its interconnected pin is rotatably driven in unison with the rotor and such that a selectable portion of the interconnected pin is rotated within the flow of injection fluid that is routed to the gate, wherein driving the first actuator includes the controller driving the first actuator and the linear or axial driver and closure valve pin upstream and downstream between a fully closed position where flow of the injection fluid is stopped, a fully open position at which a rate of flow of the injection fluid is fully open and variable positions intermediate the fully open and fully closed positions at which a ate of flow of the injection fluid varies between stopped and fully open
32. The method of claim 31 further comprising mounting the second actuator such that the axis of the rotor is generally coincident with an axis of an inlet from the injection molding machine that communicates flow of injection fluid from the machine to the manifold.
33. The method of claim 31 further comprising interconnecting the second valve pin to the rotor.
34. The method of claim 31 further comprising mounting the second actuator to the first actuator, interconnecting the closure valve pin non-rotatably to the rotor of the second actuator and adapting the second actuator and the closure valve pin to travel along the axial path of travel together with the axial driver of the first actuator.
35. The method of claim 31 wherein the second valve pin is formed to comprise an elongated shaft having an outer circumferential surface having discontinuous protrusions, grooves, projections, fins or apertures that generate a selected turbulence in the injection fluid flowing over the outer circumferential surface when the valve pin is rotated around its pin axis.
36. The method of claim 31 wherein the head of the pin interconnected to the rotor is adapted to rotates around the rotation axis in unison with rotation of the rotor.
37. The method of claim 31 further comprising instructing the actuators to drive the one or the other or both of the closure valve pin and the second valve pin according to a predetermined profile of axial travel or rotation over the course of an injection cycle.
38. An injection molding apparatus comprising an injection molding machine, a manifold that receives injection fluid from the machine and routes the injection fluid through a fluid flow channel communicating with a gate to a cavity of a mold, a first actuator and a second actuator, a valve pin having a pin axis interconnected to at least the first actuator, the actuators and the valve pin being arranged for controllably driving the closure valve pin axially upstream and downstream through the flow channel such that a distal tip end of the valve pin is driven into and out of a position that closes flow through the gate, the first actuator having an axial driver drivable along a reciprocal path of axial travel, the second actuator being mounted to the axial driver such that the second actuator is driven along the path of axial travel, the valve pin being mounted to the second actuator such that the valve pin is drivable along the path of axial travel, the second actuator comprising a rotor that is rotatably drivable around an axis coincident or parallel to the path of axial travel of the valve pin, the rotor of the second actuator being interconnected to the valve pin such that a selected portion of the valve pin is disposed within the fluid flow channel leading to the gate and the selected portion of the valve pin is rotatably drivable to rotate the selected portion of the pin within the fluid flow channel to agitate injection fluid flowing through the channel, a controller programmed to controllably drive the first actuator and the linear or axial driver and valve pin upstream and downstream between a fully closed position where flow of the injection fluid is stopped, a fully open position at which a rate of flow of the injection fluid is fully open and variable positions intermediate the fully open and fully closed positions at which rate of flow of the injection fluid varies between stopped and fully open.
39. The apparatus of claim 38 wherein the valve pin is comprised of an elongated shaft having an outer circumferential surface having discontinuous protrusions, grooves, projections, fins or apertures that are disposed within a fluid flow channel, the valve pin being controllably rotatable to rotate the protrusions, grooves, projections, fins or apertures within the injection fluid flowing through the fluid flow channel and to generate a selected turbulence in the injection fluid when the valve pin is rotated around its pin axis.
40. The apparatus of claim 38 wherein the first and second actuators are driven individually or collectively by hydraulic fluid, pneumatic fluid or an electric motor.
41. An injection molding apparatus comprising an injection molding machine, a manifold that receives injection fluid from the machine and routes the injection fluid through a flow channel communicating with a gate to a cavity of a mold, a first actuator and a second actuator, a closure valve pin having a pin axis, the closure valve pin being adapted to be controllably driven upstream and downstream along an axial path of travel through the flow channel such that a distal tip end of the closure valve pin is driven into and out of a position that closes flow through the gate, the first actuator having a linear or axial driver drivable along a reciprocal path of travel coincident or parallel to the axial path of travel, the closure valve pin being interconnected to the first actuator such that the closure valve pin is driven along the axial path of travel and reciprocally upstream and downstream into and out of the position that closes flow through the gate, the second actuator comprising a rotor having a rotation axis, the rotor being interconnected to either the closure valve pin or to a second valve pin such that either the closure valve pin or the second valve pin is rotatably driven in unison with the rotor around the rotation axis, the closure valve pin or second valve pin that is interconnected to the rotor being disposed and rotatable within the flow of injection fluid flowing through the flow channel, a controller interconnected to the first actuator that controls movement of the first actuator at least in part according to instructions that instruct the first actuator to move the closure valve pin continuously upstream at one or more selected intermediate velocities over the path of travel of the closure valve pin from a downstream gate closed position to an intermediate upstream gate open position, the controller further controlling movement of the first actuator continuously upstream from the intermediate upstream gate open position to a fully open position at one or more velocities that are higher than the one or more selected intermediate velocities.
42. The injection molding apparatus of claim 41 further comprising a sensor that generates one or more signals indicative of the position of the closure valve pin, the controller receiving the one or more signals and carrying out instructions using the one or more signals to control movement of the closure valve pin.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0056] The above and further advantages of the invention may be better understood by referring to the following description in conjunction with the accompanying drawings in which:
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DETAILED DESCRIPTION
[0067]
[0068] A linear actuator 90 having a linear driver or piston 92 that is controllably drivable in an upstream-downstream reciprocal manner along an axis A that is in-line with the flow channel or bore of the nozzle 60 is mounted in a stationary position relative to either a top clamp plate 12 or the manifold 50. In the embodiment shown in
[0069] The valve pin 120 is connected to the rotor 102 via a head 122 such that the valve pin 120 moves or translates in unison axially A with axial movement of the piston 92 and rotary actuator 100. The distal tip end 124 of the valve pin 120 is moved axially into and out of a closed gate position during the course of an injection cycle axial movement A of piston 92, actuator 100 and its interconnected valve pin 120. The head 122 of the valve pin 120 is connected to the rotor 102 in a manner such as shown in
[0070] The pin 120 is adapted not to rotate relative to rotor 102 of
[0071]
[0072] In the
[0073] In the
[0074] As shown in
[0075] Regarding the
[0076] In a preferred embodiment, the controller 300 is programmed to controllably drive the actuator 90 and linear or closure valve pin 120 upstream and downstream between a fully closed position where the rate of flow of the molten plastic 15 is stopped, a fully open position at which rate of flow is fully open and variable positions intermediate the fully open and fully closed positions at which rate of flow of the molten plastic varies between stopped and fully open. The program contained in the controller can include instructions that enable the user to control the position of the tip end 124 of the valve pin at any selected profile of positions that vary the rate of flow of injection fluid 15 through the gate 70 which in turn vary according to any predetermined profile of rates that are less than the maximum rate of flow that correspond to the profile of pin positions such as described in U.S. Pat. No. 6,464,909 and international applications PCT/US2011/062099 and PCT/US2011/062096, the disclosures of which are incorporated herein by reference as if fully set forth herein.
[0077] The second actuator 100, 150 typically includes a rotor 102, 152 having a rotation axis A, IA, the rotor being interconnected to either the closure valve pin 120 or to a second valve pin 160 such that either the closure valve pin 120 or the second valve pin 160 is rotatably driven in unison with the rotor 102, 152 around an axis that is coincident with A or parallel IA to the pin axis or axial path of travel A of the closure pin.
[0078] The closure pin 120 or second pin 160 is preferably interconnected to the rotor 120, 152 and arranged and mounted such that a portion of the valve pin having grooves, protrusions, fins or the like is disposed and rotates R within the flow of injection fluid 15 that is routed through the manifold 50.
[0079] The second actuator 152 can be mounted such that the axis of the rotor 152 is generally coincident IA with an inlet that communicates flow of injection fluid 15 from the machine 20 to the manifold 50.
[0080] The second actuator 152 can be interconnected to the second valve pin 160.
[0081] The second actuator 100 can be mounted to the first actuator 90 where the closure valve pin 120 is non-rotatably interconnected to the rotor 102 of the second actuator 100 and the second actuator 100 and the closure valve pin 120 are adapted to travel along the axial path of travel A together with the linear or axial driver 92 of the first actuator 90.
[0082] The second valve pin 160 can comprise an elongated shaft having an outer circumferential surface having discontinuous protrusions 123, grooves 129, projections, fins or apertures one or more collectively 162 that are disposed within a fluid flow channel leading to the gate and generate a selected turbulence in the injection fluid 15 flowing through the channel and over the outer circumferential surface of the valve pin when the valve pin 160 is rotated R around its pin axis IA.
[0083] The closure valve pin 120 typically comprises an elongated shaft having an outer circumferential surface having discontinuous protrusions 123, grooves 129, projections, fins or apertures one or more collectively 127 that are disposed within a fluid flow channel leading to the gate and generate a selected turbulence in the injection fluid 15 flowing over the outer circumferential surface when the valve pin 120 when rotated around its pin axis A.
[0084] The head 122 of the pin 120, 160 that is interconnected to the rotor 102, 152 is preferably interconnected such that the pin rotates R around the rotation axis A, IA in unison with rotation of the rotor.
[0085] One or the other or both of the actuators 90, 100, 150 can be interconnected to a controller 300 that controllably instructs the actuators to drive the one or the other or both of the closure valve pin 120 and the second valve pin 160 according to a predetermined profile of axial travel or rotation.
[0086] With reference to
[0087] The controller 300 includes circuitry or a program that enables the user to control the linear and rotational speed, velocity and linear and rotational positioning of the valve pin at any and all linear, axial and rotational points and positions during the course of an injection cycle. A controller, as used herein, refers to electrical and electronic control apparati that comprise a single box or multiple boxes (typically interconnected and communicating with each other) that contain(s) all of the separate electronic processing, memory and electrical signal generating components that are necessary or desirable for carrying out and constructing the methods, functions and apparatuses described herein. Such electronic and electrical components include programs, microprocessors, computers, PID controllers, voltage regulators, current regulators, circuit boards, motors, batteries and instructions for controlling any variable element discussed herein such as length of time, degree of electrical signal output and the like. For example a component of a controller, as that term is used herein, includes programs, controllers and the like that perform functions such as monitoring, alerting and initiating an injection molding cycle including a control device that is used as a standalone device for performing conventional functions such as signaling and instructing an individual injection valve or a series of interdependent valves to start an injection, namely move an actuator and associated valve pin from a gate closed to a gate open position. In addition, although fluid driven actuators are employed in typical or preferred embodiments of the invention, actuators powered by an electric or electronic motor or drive source can alternatively be used as the actuator component. The user can program the controller 300 via data inputs on a user interface to instruct the actuators 90, 100 to drive pins 120, 160 according to any predetermined profile of positions, velocities and the like.
[0088] As shown in
[0089] Further in accordance with the invention there is provided an apparatus for controlling the rate of flow of a fluid mold material from an injection molding machine to a mold cavity, the apparatus comprising:
[0090] a manifold receiving the injected fluid mold material, the manifold having a delivery channel that delivers the fluid mold material to a gate to the mold cavity;
[0091] an actuator interconnected to a valve pin having a tip end, the actuator moving the valve pin continuously upstream along a path of travel between a downstream gate closed position and an intermediate upstream gate open position, the downstream gate closed position being a position wherein the tip end of the valve pin obstructs the gate to prevent fluid material from flowing into the mold cavity, the intermediate upstream gate open position being a predetermined position between the downstream gate closed position and a fully open, end of stroke position upstream of the intermediate upstream gate open position at which the fluid mold material flows at a maximum rate through the gate;
[0092] a controller interconnected to the actuator that controls movement of the actuator at least in part according to instructions that instruct the actuator to move the valve pin continuously upstream at one or more selected intermediate velocities over the course of travel of the valve pin from the downstream gate closed position to the intermediate upstream gate open position;
[0093] the controller further controlling movement of the actuator continuously upstream from the intermediate upstream gate open position to the fully open, end of stroke position at one or more velocities that are higher than the one or more selected intermediate velocities.
[0094] Such an apparatus preferably further comprises a sensor that generates one or more signals indicative of the position of the valve pin, the controller carrying out instructions to cause the valve pin to move continuously upstream at the one or more selected intermediate velocities and to adjust upstream velocity of the valve pin based on one or more of the signals generated by the sensor.
[0095] The instructions of the controller can utilize the signals received from the sensor to calculate real time velocity of the valve pin and compare the calculated real time velocity to one or more predetermined velocities for the pin during the course of travel of the tip end of the pin from at least the downstream gate closed position to the intermediate upstream gate open position. In such an embodiment, the controller preferably compares the calculated real time velocity to the predetermined velocities and sends a signal instructing the actuator to match the velocity of the pin to the predetermined velocities based on the comparison at any given position of the valve pin. In such an embodiment the instructions and the sensor signals comprise a closed loop control. In such an embodiment, the controller calculates real time velocity based a value corresponding to the position of the pin signal received in real time from the sensor.
[0096]
[0097] In alternative embodiments the controller can include a processor and instructions that receive the pin position information and signals from the position sensor and calculate the real time velocity of the pin from the pin position data in real time at one or more times or positions over the course of the pin travel through the RP, RP2, RP3 path length and/or beyond. Typically such calculations of velocity are continuous throughout the cycle. In such an embodiment, the calculated pin velocity is constantly compared to a predetermined target profile of pin velocities and the velocity of the pin is adjusted in real time by the controller 16 to conform to the profile. In this embodiment as in all previously described embodiments, the pin is moved continuously upstream at all times between the gate closed position and all positions upstream of the gate closed position. Such control systems are described in greater detail in for example U.S. Patent Publication no. 20090061034 the disclosure of which is incorporated herein by reference.